1. Field of the Invention
The present invention relates to a communication terminal having an email-message sending-and-receiving function, and more particularly to a method and a program which perform destination-address right/wrong determination of an email message.
2. Description of the Related Art
Now, email via a communication network such as the Internet has widely become popular as a communication tool even for communication terminals such as mobile phones as well as personal computers (PC). Nowadays, email has become indispensable for most people. (Hereinafter, email messages are also simply referred to as messages.)
In recent years, such communication terminals receive a large number of so-called unsolicited email messages (spams) sent for advertising, fraud, or the like regardless of a user's intentions. As a result, email messages that the user wishes to read are buried among the unsolicited email messages.
In order to cope with such unsolicited email messages, most email software programs have a received-message filtering function. As an example of such a received-message filtering function, there is a received-message filter to which a Bayesian approach is applied and which automatically determines whether an email message is an unsolicited email message or not on the basis of a subject or a message body of the email message. With regard to such a received-message filter, it is necessary for a user who uses the email software program to manually determine whether or not each email message received is an unsolicited email message for a certain period of time at the beginning. After sufficient information used for the automatic determination is stored as the result of the user's manual determination, the received-message filter automatically determines whether or not each email message received is an unsolicited email message at the time of receiving the email message. The determination is performed on the basis of whether or not a subject or a message body of an email message just received includes certain words that are included a large number of times in subjects or message bodies of the unsolicited email messages received in the past. If the email message just received includes the certain words, the email message just received is determined as an unsolicited email message.
One advantage of email is that a message is delivered instantly after performing a sending operation. However, if a message has a wrong destination address, that is also delivered instantly after performing the sending operation. Recent email software programs (mailers) are designed to select a destination address easily from an address book or the like. Thus, the probability of selecting a wrong destination address has been increased. In a real-world situation, personal information or confidential information is often sent by email, and thereby such information may be leaked by selecting a wrong destination address.
It has been necessary for a user to check that a message has a right destination address by himself/herself in order to prevent the message from being sent to a wrong destination address.
In order to deal with such a problem at the time of sending a message, the following technique has been proposed. Destination addresses that have a high probability of being mistakenly selected are marked in advance and if a user tries to send a message to one of the marked destination addresses, the user is requested to check whether it is permitted to send the message thereto (see Japanese Unexamined Patent Application Publication No. 11-243412).
Another technique for an email sending operation has also been proposed. When an email message is requested to be sent, by delaying start of the sending operation, a user is given a certain amount of time to cancel the sending operation in the case that the user notices the message is going to be sent to a wrong destination address (see Japanese Unexamined Patent Application Publication No. 2003-157216).